'Korengal' filmmaker Sebastian Junger (Tim Hetherington)

Junger's recent TED talk

When Army paratrooper Sgt. Brendan O’Byrne returned from a tortured year of combat in Afghanistan’s deadly Korengal Valley, he looked into the lens of a video camera and wondered out loud whether God hated him for what he had done there.

“I’m not religious or anything, but I felt like there was hate for me, because I did ...” O’Byrne says, pausing, “... sins. I sinned. And although I would have done it the same way — everything the same exact way — I still feel this way.

“That’s the terrible thing with war. You do terrible things, then you have to live with them afterwards. But you’d do it the same way if you had to go back.”

Despite those conflicting emotions, a part of O’Byrne wanted to go back.

That’s something author, filmmaker and war correspondent Sebastian Junger would hear again and again from troops returning from combat: They missed it.

In his new documentary “Korengal,” Junger explores that paradox among warfighters who have learned to hate war — but love combat.

Junger’s Oscar-nominated 2010 documentary “Restrepo” followed O’Byrne and his platoon of troops through their deployment to a remote mountaintop outpost during some of the worst fighting in Afghanistan.

“Korengal” picks up where “Restrepo” leaves off, not so much as the next chapter in the story of those troops, but as a way to delve more deeply into what they went through.

“It’s meant to be complementary to ‘Restrepo,’ ” Junger tells OFFduty. “ ‘Restrepo’ is mostly for civilians to give them a sense of the experience of combat. ‘Korengal’ is more for the soldiers themselves, to inquire more deeply into their experience and how it affected them.”

The blessing of combat

While often hated in the moment, combat deployments become a blessing of sorts, Junger says. There is a clarity of focus and purpose that comes with war that few in civilian life will ever know. Mix that with daily doses of high adrenaline and a kind of pure loyalty among those you fight alongside, and combat is a perfect baptism into tribal brotherhood.

Many troops may not even like those they serve alongside, but there is a certainty among them that each would not hesitate to die for the other, Junger says.

But that blessing becomes a curse when they return home.

“They miss the brotherhood — that incredibly close bond between 30 guys in combat. And real intimacy. From the bunk I slept in at Restrepo I could reach my arm out and touch three other men. We were really close — physically and emotionally close. It’s kind of terrifying to be in such an emotionally safe environment and then suddenly be expelled into an alienated, fractured, empty American society,” Junger says.

“We have the highest rates of suicide, depression and child abuse — and now mass killings — ever in human history. It’s crazy. And that’s the society these guys are coming back to.”

Like a fish who has known only dirty water, war provides an ironic clarity of what life could be like. But redeploying to the dirty water back home becomes heartbreaking.

“I think they’re seeing our society clearly for the first time, because they’ve experienced the opposite in combat. They’re seeing the alienation. They’re experiencing the loneliness.”

And for many vets, that’s more frightening than combat ever was.

Scarier than bullets

“Feeling alone and alienated — that’s scarier than bullets. They know how to deal with bullets, and in combat they’re dealing with bullets together. But now they’re dealing with their loneliness, by definition, alone. And that’s way scarier,” Junger says.

While helping troops wrestling with post-traumatic stress is important, he goes on, “It makes me think, at the end of the day, who really has the problem, us or them? Who really needs to be healed? I’m not talking about healing from the trauma of, say, seeing someone’s leg blown off. That’s a whole other thing. I’m talking about the sense of alienation when they come home.”

Most Israeli soldiers returning from combat don’t have that problem, he points out.

“My guess is it’s because everyone serves in the military and they come back to a society that’s coherent, in a defensive posture, and everyone is involved. So there’s no readjustment. Most ancient tribal societies were the same way.”

He’s hopeful, though, that troops can find at least a little of what they’re missing without returning to combat.

'The Last Patrol'

That’s the thrust of another documentary that Junger has just completed. Dubbed “The Last Patrol” and slated to air on HBO in November, Junger and O’Byrne — now best friends — embark, along with two others, on a trek up the northeast backbone of the country.

“We decided to walk from [Washington] D.C. to Philadelphia to Pittsburgh, hiking only along the railroad lines. We weren’t hopping freight cars, we were walking, and walked the whole way.”

“Which,” he points out, “is totally illegal. The cops were looking for us. At one point they had a helicopter looking for us.”

The four-man team used no tents, bathing in rivers along the way, sleeping under culverts and in abandoned buildings, in what Junger calls “a kind of high-speed vagrancy.”

It was, he admits, “a really weird experiment.”

But a valuable one. “We had a 400-mile conversation about war and why it’s so hard to give up and come home,” he says.

As a war correspondent, it’s something Junger wrestles with, too. Or least he did.

He promised his wife that he would stop deploying after his year in Afghanistan filming “Restrepo” with co-filmmaker and photographer Tim Hetherington

It was a promise he found hard to keep. Until, that is, Hetherington was killed covering the fighting in Libya in 2011.

“Before, I was doing it for my wife, reluctantly, and then after Tim got killed, I didn’t want to anymore. I didn’t want to devastate everyone who loves me. At some point you have to start living with other people’s concerns foremost.”

Working on “The Last Patrol” over the past year helped him find new ways to feed that hunger.

“I learned you can truly reproduce the brotherhood of combat if you just make things hard enough. Just twist that dial all the way to the right, and you can do it. It’s unsettling enough to wonder where you’re going to get your water and dealing with the weather and hunger that it does truly bond you. It was really therapeutic for all of us.”

It’s something he thinks others can replicate by hiking, climbing mountains and other extreme sports.

“This will be awfully un-PC of me, but I think men need to get out and be by themselves sometimes. I think one of the things they miss is being in an all-male group separated from all their other concerns for a while, just with the guys.

“There is enormous therapeutic value to that. It’s not like they’re sitting around holding hands, working things out. But the time spent with other men is hugely valuable, and the more marginal you are” — the further removed you are from normal living — “the more intense that is.”

“Korengal” is opening in limited release at dozens of theaters throughout the summer, with particular focus on military communities. Check korengalthemovie.com for screening dates.